The prostaglandins are a group of hormone-like substances which may be viewed as derivatives of prostanoic acid. Several prostaglandins are found widely distributed in mammalian tissue and have been isolated from this source. These prostaglandins have been shown to possess a variety of biological properties such as bronchodilation and the ability to reduce gastric secretion.
The present invention concerns prostaglandin E.sub.1 and prostaglandin E.sub.2 (PGE.sub.1 and PGE.sub.2) derivatives in which the 9-position (using the prostanoic acid numbering system) remains intact as a carbonyl group; the 11-position bears an ethynyl group, i.e. the 11-hydroxyl group normally present in PGE.sub.1 and PGE.sub.2 has been removed and is replaced with an ethynyl group; and there is either a methyl or an ethynyl group at the 15-position in addition to the normally present hydroxyl group.